Yarn severing arrangement for textile spindles



Jan. 27, 1970 P. KRAUSS ET AL YARN SEVERING ARRANGEMENT FDR TEXTILE SPINDLES Fild Nov. 29, 1968 M van for M Muse sr' Ron- United States Patent 3,491,526 YARN SEVERHNG ARRANGEMENT FOR TEXTILE SPINDLES Paul Krauss, Ebersbach, and Ernst Roethke, Schorndorf,

Germany, assignors to Zinner-Textiimaschinen Gesellschaft mit beschrankter Haftnng, Ebersbach, Germany Filed Nov. 29, 1968, Ser. No. 780,004 Claims priority, application Germany, Dec. 1, 1967, Z 13,183 Int. Cl. D0111 7/18 U.S. Cl. 57131 22 Claims ABSTRACT OF THE DISCLOSURE A yarn end extending between an underwinding portion of a spindle and a yarn package on a tube carried by the spindle, is severed during the dofiing of the tube by a holder which is frictionally coupled with the tube and moved by the same to a position holding the yarn end against circumferential movement until the yarn end breaks.

BACKGROUND OF THE INVENTION The present invention relates to a textile spindle which is constructed to obtain the severing of a yarn end extending between the underwinding portion of the spindle and a package of the same during the dofiing of the tube carrying the package.

The term tube is used in the present application to cover any kind of carrier or holder for a wound yarn, including tapered conical tubes, spools and the like, which can be attached to rotary textile spindles for winding up yarn until a yarn package is formed. The present invention is particularly concerned with textile machines, such as ring spinning machines and thread twisting machines provided with automatic donning and doffing apparatus by which tubes with complete yarn packages are automatically exchanged for empty tubes on the spindles. The term yarn is used in the present application to cover yarns and twisted threads, as well as synthetic fibers consisting of one or several endless filaments.

In textile machines of the type to which the present invention relates, the yarn end of a fully wound Yarn package is wound on an underwinding portion of the spindle. When the tube with the complete yarn package is dotted from the spindle, the yarn portion between the package and the underwinding portion of the spindle, must be torn or severed. If the yarn does not break and is unwound from the package during the doffing of the tube and package, the exchange of tubes may be substantially disturbed. For example, while the full tubes are transported to a storing place, they may be held back and tilted by the yarn end still fixed to the underwinding portion, and damaged by colliding with machine parts. If the yarn end breaks only very late, for example when the full tube has been placed on a conveyor by which the full tubes are transported to a storing place, the yarn end is elastically tensioned and recoils when the yarn end breaks so that the yarn portion connected to the unwinding portion of the spindle entangles the spindle so that the following winding operation cannot be properly carried out, and the machine must be stopped for clearing the respective spindle.

In order to assure a more reliable severing of the yarn end during the doffing of a full tube, it is known to provide the spindle with a spindle flange located above and adjacent the underwinding portion of the spindle and having a roughened or knurled periphery whose projections retain the yarn end so that the same breaks. However, it has been found that this construction does not entirely prevent the unwinding of yarn from the package during Patented Jan. 27, 1970 the dofiing of the tube with the package so that frequently the yarn end is not broken or severed early enough.

SUMMARY OF THE INVENTION It is one object of the invention to overcome the disadvantages of prior art constructions for severing a yarn end portion of a yarn package during the doffing of a tube from a spindle, and to provide an arrangement by which severing of the yarn end is reliably obtained.

Another object of the invention is to obtain the severing of the yarn end during the early part of the dofiing of the tube with the yarn package.

Another object of the invention is to prevent unwinding of yarn from the package during the dofiing of the tube carrying the package.

Another object of the invention is to prevent circumferential movement of the yarn end portion about the spindle so that unwinding of yarn from the yarn package is not possible during the dotting of the tube.

With these objects in view, the present invention provides a method by which a yarn portion fixed to an underwinding portion of a textile spindle and extending from the same to a yarn package wound on a tube carried by the spindle is severed. In accordance with the invention, the yarn portion is held against circumferential movement about the spindle and the tube, while the tube and package on the same are simultaneously dotted away from the underwinding portion of the spindle so that the yarn is not unwound from the yarn package and the yarn portion is longitudinally stressed and severed. Since the yarn portion cannot be lengthened by additional yarn unwound from the package, it is severed during the first part of the dofling movement of the tube in longitudinal direction of the spindle.

By applying the method of the invention, yarns having very high tensile strength, for example synthetic yarns, are reliably severed during the dofling of the tube. Consequently, when the method of the invention is applied in textile machines with automatic doffing and donning apparatus, the above-described disturbances which occur in arrangements according to the prior art are reliably prevented.

It is advantageous that the yarn portion is stressed and severed during the first part of the dofiing movement of the tube when the axial displacement of the tube on the spindle is comparatively small. This result can be obtained by preventing circumferential movement of the yarn portion along a short predetermined distance in axial direction of the spindle, which corresponds to the first part of the doffing movement of the tube with the package.

One embodiment of an apparatus according to the invention comprises a textile spindle having an underwinding portion, a carrier portion for supporting a tube with a yam package having a yarn end wound on the underwinding portion, and a guide portion between the carrier portion and the underwinding portion; and a yarn holder mounted on the guide portion of the spindle for movement in axial direction of the s indle between a normal position adjacent the underwinding portion and an operative position adjacent the carrier portion of the spindle. The holder has a coupling portion, preferably a cylindrical bushing. frictionally engaged in the normal position of the holder by the tube, and a holding portion, preferably a flange, formed with circumferentially spaced recesses for receiving a portion of said yarn end between the yarn package and the underwinding portion.

During doffing of the tube and package from the carrier portion of the spindle, the holder is moved by the tube to the operative position while holding the yarn end substantially in the same circumferential position until the yarn end breaks. During further movement of the tube in the dofiing direction, the tube releases the coupling portion of the holder so that the same returns to its normal position, preferably by the action of the force of gravity. e 1

It is advantageous to provide the holding portion with teeth between which wedge-shaped recesses are formed for clamping the yarn end. Y

In a modified embodiment of the invention, the coupling portion of the holder is omitted, andithe holding portion is fixedto the lower end ofithe tube carrying the package However, this construction has the disadvantage that the teeth which form the recesses of the holding portion, may damage the packages on other full tubes transported to a storing place. I In the preferred embodimentiof the invention, the holder is connected with the tube while the tube is seated on the carrier portionof the spindle, While during the doffing of the tube, the holder moves in axial direction with the tube until stopped by an abutment on the spindle, whereupon the tube separates from the coupling portion 9f the holder during further dofling movement.

In the preferred embodiment of the invention the coupling portion of the holder isa bushing mounted on a cylindrical guide portion of the spindle, and fitting into the inner surface of the lower end of the tube. The frictional connection between the tube and the coupling bushing is improved if the bushing is resilient, or is provided with one or;several resilient spring rings which resiliently press against the inner annular surface of the tube end portion. In some cases, the bushing has a shape matching ,the shape of the inner surface of the tube so that the tube engages the bushing with a tight fit.

It is advantageous to limit the axial movement of the holder by spaced abutments to a distance which is between one-quarter and one-twentieth of the axial length of the tube.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary elevation illustrating a textile spindle provided with a yarn holder according to the invention, shown in a normal position;

FIG. 2 is a fragmentary elevation illustrating the spindle of FIG. 1 with the holder in a ditferent position;

FIG. 3 is a fragmentary elevation illustrating the spindle of FIG; 1 with the holder in an end position;

FIG. 4 is a fragmentary elevation illustrating a modified embodiment of a holder provided with a resilient coupling portion;

FIG. 5 is a fragmentary elevation, partially in section, illustrating a modified holder according to the invention; FIG. 6 is a cross-sectional view taken on line 66;

FIG, 7 is a fragmentary plan view illustrating a first construction of the holding portion of the holder on an enlarged scale;

FIG. 8 is a plan view illustrating on an enlarged scale the holder used in the embodiment of FIG. 1;

FIG. 9 is a fragmentary elevation, partially in section, illustrating a further embodiment of a holder according to the invention; and

FIG. 10 is a fragmentary plan view illustrating on an enlarged scale, a modified construction of the holding portion of the holder.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to the embodiment illustrated in FIGS. 1 to 3 and FIG. 8, a rotary textile spindle 3 has a journal portion 4 projecting into a bearing, not shown, a pulley portion 7, a knurled under-winding portion 1, a knurled spindle flange 2, a carrier portion 9, and a cylindrical When the spindle is rotated by a cord passing over pulley portion 7, a yarn package 17 is wound on a tube 6 which i is seated on carrier portion 9 and rotates with thessame so that the yarn is wound up to form a package on tube 6. When the package is completed, several loops of the yarn end 19 are Wound on the underwinding portion 1 to anchor the yarn end, anda yarn portion 19 extends between the underwinding portion 1 and yarn package 17.

The holding flange .11 of holder 10 is provided with peripheral teeth and recesses 16, as best. seen in FIG. 8. The cylindrical bushing 13 has an outer diameter matching the inner diameter of the lower end portion of tube 6 so that, when tube 6 is donned onto the spindle, the circular inner surface of the lower tube end portion frictionally engages the outer surface of bushing 13 while the lower annular edge of tube 6 abuts an upper annular abutment face of flange 11. The engagement between the lower endportion of tube 6 and the outer surface of bushing 13 is a tight fit so that holder 10 is frictionally coupled with tube 6. When the package 17 has been wound; and a few anchoring loops have been formed in the usual manner on the knurled underwinding portion 1, rotation of the spindle is stopped, and a dofling apparatus, not shown, of conventional construction, engages tube 6 and doffs the same together with the package in the direction of the arrow A. 5

Since the coupling bushing 13 of holder 10 is at the beginning of the doffing movement frictionally coupled with the lower end of tube 6, holder 10 moves with tube 6 in the direction of the arrow while the portion of yarn end 19 located in a recess 16 of the hdlding flange 11, is tensioned, as is apparent from a comparison between FIGS. 1 and 2. The yarn portion 19 cannot move in circumferential direction about the tube and the spindle, since it is held in a recess 16 of holder 10, which is nonturnable since it is coupled with tube 6 which is doffe-d from carrier portion 9 Without any angular movement. Since yarn portion 19 cannot turn about the package 17, no additional yarn is unwound, and yarn portion 19 is tensioned during the dofling movement and breaks quickly. When holder 10' abuts the annular abutment shoulder 14, it cannot further move in axial direction with the dotted tube, and the lower tube end portion 5 slides in axial direction off coupling bushing 10, as shown in FIG. 3. As soon as coupling bushing portion 13 is released by the lower tube end portion 5, holder 10 drops back to its normal position resting on spindle flange 2 so that an empty tube 6 can be placed by donning apparatus on carrier portion 9, frictionally engaging with the lower tube end portion 5 the coupling bushing 13 of holder 10.

The holder shown in FIG. 7 has peripheral teeth 61 and corresponding recesses 60, each of which includes an inner guiding portion for the yarn portion 19, and a slot between the wider outer ends of teeth 61 through which the yarn portion 19 enters the guide parts of recesses 60. As soon as the yarn portion 19 has entered a guide portion of recess 60, it is reliably held against circumferential movement about tube 6 and spindle 3, and escape of the yarn portion 19 from the recesses is impossible so that the tensile stress applied by the dotted tube to yarn portion 19 reliably severe the same.

The modified holder 25 shown in FIG 4 has a coupling bushing 38 with a toric coupling surface, and is made resilient and elastic by slots forming resilient strips 37. Holding flange 36 may be constructed as shown in FIG. 8. When tube 6 is donned and tube end portion 5 engages coupling bushing 38, the strips 37 are resiliently deformed, and a tight frictional engagement between the tube and holder 25 is assured.

FIGS. 5 and 6 illustrate another embodiment of the invention in which holder 26 is drawn of sheet metal. A cylindrical guide portion 35 of the spindle extends between the annular abutment shoulder of carrier portion 9', and the spindle flange 2' provided adjacent the underwinding portion 1. Holder 26 has a cylindrical coupling bushing portion 33 having an inner flange 32 at the upper end, and an outer flange 27 at its lower end which in the normal position of holder 26 abuts spindle flange 2'. The outer flange 27 has circumferentially spaced small recesses and projections 28 for holding a yarn portion 19 against circumferential movement. The cylindrical guide portion 35 is stepped and has a portion 34 of greater diameter so that the bushing 33 is guided on portion 34, and the inner flange 32 is guided on the thinner part of guide portion 35 until abutting the shoulder on the upper end of guide portion 35 formed by the carrier portion 9. FIG. 9 illustrates another embodiment of the invention in which a holder is mounted on a cylindrical guide portion 9" of the spindle, which has a knurled spindle flange 2 and an underwinding portion 1". Holder 10' has an inner coupling bushing portion 40 and an outer holding portion 50 which form a circular slot with coupling bushing 40, and has a flange 55 provided with circumferential recesses and projections, and surrounding a portion of the outer periphery of spindle flange 2". The upper end of coupling bushing 40 tapers so that the tube 41 is guided into the circular slot 51. Coupling bushing 40 has a circumferential groove 53 in which a spring ring 54 is mounted which frictionally and resiliently engages the inner surface of the lower tube end portion 42 so that holder 10' is frictionally coupled with tube 41 and moves with the same during the dofling of tube 41 with the yarn package, while the yarn portion, not shown in FIG. 9, between the package and the underwinding portion 1 is located in one of the peripheral recesses of flange 55 and prevented from circumferential unwinding movement.

The arrangement of FIG. 9 has the advantage that there can be no open annular gap between the lower end of the tube and the holding flange, which may occure between the tube end portion 5 and the holding flange 11 in the construction of FIG. 1. Furthermore, in the construction of FIG. 9, any annular gap which may form between spindle portion 2' and holder 10, is covered by a portion of flange 55. It has been found advantageous to provide peripheral recesses and projections only in the lowermost flange 55 of the holding portion 50.

In the embodiment illustrated in FIGS. 1 to 3, the teeth and recesses 16 of flange 11 project only slightly in radial direction beyond the outer diameter of the lower tube end portion 5, which has certain advantages. The spindle flange 2 serves the purpose to prevent unwinding of the yarn loops on underwinding portion 1. If such unwinding is not to be expected, spindle flange 2 may be omitted.

In FIGS. 1 to 3, the outer diameter of spindle flange 2 is greater than the outer diameter of the underwinding portion 1, but at the same time, the outer diameter of spindle flange Z is smaller than the outer diameter of the holding flange 11. The outer diameter of the spindle flange 2 is substantially the same as the outer diameter of the coupling bushing 13, and the inner diameter of the tube end portion 5 which is particularly advantageous for this embodiment. In the embodiment of FIG. 5, substantially the same relative dimensions are used, while in the embodiment of FIG. 9, the outer diameter of the holding flange 55 is substantially greater than the outer diameter of the tube end portion 42, which is advantageous in the arrangement of FIG. 9.

In many cases it is advantageous to provide sharp edges 'on the peripheral teeth of the holding flanges which favors the severing of the yarn. When a yarn is guided in the recesses 16 of the holder construction shown in FIG. 8, longitudinal movement of the yarn is braked, and the yarn may be clamped or severed if the teeth are sharp enough. In order to obtain a reliable clamping of the yarn and blocking of longitudinal movement so that the yarn breaks due to the tensile stress, the teeth and recesses may be constructed to obtain reliable clamping of the yarn. As shown in FIG. 10, the peripheral teeth of the holder have such a shape as to form wedge shaped recesses 64 in which the yarn is clamped. On the other hand, in the embodiment of FIG. 6, the yarn is guided for longitudinal movement in the wide guide portions of recesses 60. The shape of the recesses and teeth of the holder is selected in accordance with the properties of the yarn which is wound on the respective spindle.

Instead of providing one row of teeth and recesses on the holder, in many cases parallel annular rows of teeth are advantageously provided on the holding flange of the holder, and the teeth may be staggered in circumferential direction so that a circumferential displacement of the yarn is even more reliably prevented.

It Will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of yarn end severing arrangements for textile spindles differing from the types described above.

While the invention has been illustrated and described as embodied in a spindle provided with a yarn holder for preventing unwinding of the yarn from the package during the dofiing of a tube, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

What is claimed as new and desired to be protected by letters Patent is set forth in the appended claims.

1. Yarn end severing arrangement for textile spindles, comprising, in combination, a rotary spindle having an underwinding portion, and a carrier portion for supporting a tube with a yarn package having a yarn end wound on said underwinding portion; and a yarn holder movable in axial direction of said spindle and being non-rotatably connected with said tube for axial movement therewith, said yarn holder having a holding portion formed with circumferentially spaced recesses for receiving a yarn portion of said yarn end between said package and said underwinding portion so that during axial dofling of said tube and package from said carrier portion, said holder is moved by said tube away from said underwinding portion while holding said yarn portion in the same circumferential position until said yarn portion breaks.

2. Yarn end severing arrangement for textile spindles, comprising, in combination, a rotary spindle having an underwinding portion, a carrier portion for supporting a tube with a yarn package having a yarn end wound on said underwinding portion, and a guide portion bet-ween said carrier portion and said underwinding portion; and a yarn holder mounted on said guide portion for movement in axial direction of said spindle between a normal position adjacent said underwinding portion and an operative position adjacent said carrier portion, said holder having a coupling portion frictionally engaged in said normal position by said tube, and a holding portion formed with circumferentially spaced recesses for receiving a yarn portion of said yarn end between said package and said underwinding portion so that during dofling of said tube and package from said carrier portion, said holder is moved by said tube to said operative position while holding the yarn portion in the same circumferential position until the yarn end breaks whereupon said tube releases said coupling portion of said holder.

3. Yarn end severing arrangement as claimed in claim 2 wherein said spindle includes a flange portion between said under-winding portion and said guide portion; and

wherein said holding portion of said holder is located adjacent said flange portion, said flange portion having a diameter greater than the diameter of said underwinding portion and smaller than the diameter of said holding portion.

4. Yarn end severing arrangement as claimed in claim 3 wherein said diameter of said flange portion of said spindle is substantially equal to the outer diameter of said coupling portion and to the inner diameter of the portion of said tube which engages said coupling portion.

5. Yarn end severing arrangement as claimed in claim 3 wherein said flange portion of said spindle has peripheral projections for engaging and holding the yarn end.

6. Yarn end severing arrangement as claimed in claim 2 wherein said spindle has abutments at the ends of said guide portion engaged by said holder in said normal and operative positions, respectively, for stopping said holder so that said coupling portion of said holder is released by said tube during the doffing movement when said holder abuts the respective abutment in said operative position.

7. Yarn end severing arrangement as claimed in claim 6 wherein said abutments are annular shoulders, wherein said guide portion is located between said shoulders and has a smaller diameter than the same; and wherein said coupling portion is tubular and surrounds said guide portion, being slidable on the same.

8. Yarn end severing arrangement as claimed in claim 2 wherein coupling portion is a cylindrical bushing and said guide portion is cylindrical; wherein said tube has a circular end portion fn'ctionally engaging said bushing; wherein said holding portion is a circular flange projecting from said bushing and having recesses uniformly spaced along the periphery thereof; and wherein said tube has a circular edge abutting said flange in said normal position While said end portion of said tube surrounds and frictionally engages said bushing.

9. Yarn end severing arrangement as claimed in claim 8 wherein said flange is located at the end of said bushing adjacent said underwinding portion.

10. Yarn ends severing arrangement as claimed in claim 8 wherein said flange has peripheral teeth forming said recesses between each other.

11. Yarn end severing arrangement as claimed in claim 10 wherein said teeth taper outward and said recesses taper inward in radial direction of said flange.

12. Yarn end severing arrangement as claimed in claim 10 wherein said teeth have radially outer ends closer spaced in circumferential direction than the inner ends of the same so that each recess include an inner wide yarn guiding recess portion and an outer narrow recess portion for engaging the yarn end and for holding the same in said inner yarn guiding recess portion.

13. Yarn end severing arrangement as claimed in claim 2 wherein said holding portion is located at the end of said coupling portion adjacent said underwinding portion and has an abutment; and wherein said tube has an annular end portion frictionally engaging said coupling portion and having an annular edge abutting said abutment.

14. Yarn end severing arrangement as claimed in claim 13 wherein said coupling portion is tubular, and wherein said abutment is an annular shoulder radially projecting from said tubular coupling portion and in contact with said annular edge in said normal position of said holder, and during the movement of the same to said operative position.

15. Yarn end severing arrangement as claimed in claim 13 wherein said holding portion is a circular flange radially projecting from said coupling portion and having an annular shoulder adjacent the latter forming said abutment; and wherein the outer diameter of said flange is slightly greater than the outer diameter of said end portion of said tube.

16. Yarn end severing arrangement as claimed in claim 2 wherein said coupling portion is a cylindrical resilient bushing elastically deformed by said tube when the same engages said coupling portion so that said holder is coupled with said tube by a high friction force.

17. Yarn end severing arrangement as claimed in claim 2 wherein said spindle has abutments at the ends of said guide portion for stopping movement of said holder on said guide portion in said inoperative and operative positions; and wherein the distance between said abutments is between one quarter and one twentieth of the length of said tube.

18. Yarn end severing arrangement as claimed in claim 2 wherein said coupling portion having an annular outer surface frictionally engaged by the inner surface of an end portion of said tube in said normal position, and wherein said holding portion is annular and surrounds at least a portion of said inner tubular coupling portion forming with the same a circular slot in which said tube end portion is at least partly located, said annular holding portion having said recesses on the outer periphery thereof.

19. Yarn end severing arrangement as claimed in claim 18 wherein said spindle has an annular flange portion between said guide portion and said underwinding portion; and wherein said annular holding portion surrounds at least part of said annular flange portion in said normal position of said holder.

20. Yarn end severing arrangement as claimed in claim 1 wherein said holding portion has sharp peripheral teeth forming said recesses between each other.

21. Yarn end severing arrangement as claimed in claim 1 wherein said holding portion has peripheral teeth whose circumferential extension gradually increases in inward direction, said teeth forming between each other said recesses and being shaped so that said recesses are wedge shaped and adapted to clamp a yarn end located therein when said yarn end is ,tensioned by movement of said holder toward said operative position.

22. The method of severing a yarn portion fixed to an underwinding portion of a rotary textile spindle and extending from the same to a yarn package wound on a tube carried by said spindle, comprising the steps of holding said yarn portion for a predetermined distance in axial direction of said spindle against circumferential movement about said spindle and tube; and simultaneously doffing in said axial direction said tube and package away from said underwinding portion so that the yarn is not unwound from said yarn package and said yarn portion is longitudinally stressed and severed.

References Cited UNITED STATES PATENTS 964,084 7/1910 Boswell 57-131 3,210,922 10/ 1965 Winter 5754 FOREIGN PATENTS 723,383 6/ 1955 Great Britain. 1,007,616 10/ 1965 Great Britain.

DONALD E. WATKINS, Primary Examiner US. Cl. X.R. 

